Section for Week 1, Thursday, 1/14/99

STRINGS
-------

Thus far we've seen the standard "hello\n" string appear often.  What can we
do natively w/ strings in perl?  Quite a lot:

1) Within a double-quote string, we have the following constructs:
   \n	  Newline
   \r	  Return
   \t	  Tab
   \f	  form-feed
   \b	  backspace
   \a	  bell
   \e	  escape
   \007	  Octal (begin w/ zero, give three digits)
   \x7f	  Hex (begin w/ x)
   \c?	  Control-?  (so \cX == ^X)
   \\	  Backslash
   \"	  Double quote
   \l	  lowercase next letter
   \L	  Lowercase to \E
   \u	  uppercase next letter
   \U	  uppercase to \E
   \Q	  \-quote every non-alphanumeric to \E
   \E	  Ends \L \U \Q

The case constructs come in useful when variable interpolating: "\L$string\E".

Operators:
   Concatenation: "hello " . "world" == "hello world"
   Comparison: eq, ne, lt, gt, le, ge
   Repetition: "Ami" x 3 == "AmiAmiAmi"
	       (3+2) x 4 == 5 x 4 == "5" x 4 == "5555" (auto string context)

Functions:
   chop() --> take the last character off a string (must be a variable!)
	      $x="Hello World";	      
	      chop($x);		      # now $x == "Hello Worl";
   chomp() --> only remove a newline from the end of a string
	       $a = <STDIN>;
	       chomp($a);
	       Equiv: chomp($a = <STDIN>);
	       

Exercise:
	Write a program that reads a number and a string and prints out the
	string the number of times indicated by the number on separate
	lines.
Answer:
	In C, probably iterate (for loop) printing each string every
	iteration.  Compare Perl solution:

	print "What is the string? ";
	$s=<STDIN>;
	print "What is the number? ";
	$number=<STDIN>;
	print $s x $number;